Definition - What does iPhone mean?
The iPhone is a line of smartphones produced by Apple Inc. While the feature list of an iPhone is continually changing with each new model, it is best known for its touch screen that allows quick response to single or multiple finger strokes. It runs on the iOS mobile operating system.
Techopedia explains iPhone
The first iPhone was the result of a collaborative project between Apple and AT&T Mobility (known as Cingular Wireless at that time). Both the hardware and software portions of the phone was developed by Apple. The iPhone’s Unix-like operating system, iOS, is based on Mac OS X, the operating system that runs on Apple desktops and laptops.
Applications for the iPhone can be developed using the downloadable SDK (software development kit), which includes tools for developing, testing, running, debugging and tuning applications. Code can be edited, compiled and debugged using the Xcode tools. Xcode also allows developers to test apps either on an iOS device or an iOS Simulator.